Such a steering arrangement is known, for example, from EP 2 786 915 B1.
When a vehicle equipped with such a steering arrangement is steered, the driver turns a steering wheel (or any other command means). By turning the steering wheel two elements, in particular a spool and a sleeve, are moved relatively to each other to open a number of orifices in the main flow path. This allows a certain amount of hydraulic fluid to pass the main flow path. This hydraulic fluid drives the flow meter which in turn restores the initial relative positions of the two elements. Therefore, when the steered wheels have reached the position commanded by the steering wheel the main flow path is closed again.
In order to deliver more hydraulic fluid to the steering motor connected to the working port arrangement the amplification flow path is used. In the amplification flow path an orifice, so called amplification orifice, is arranged which is opened and closed in synchronism with the orifices in the main flow path. Therefore, an additional flow proportional to the flow through the main flow path can be guided through to the amplification flow path. However, even with such a hydraulic steering arrangement it is in some cases difficult to satisfy the requirements of a desired steering velocity. In particular, when a steering motor connected to the working port arrangement has a big displacement, like in big articulated steered vehicles, it is difficult to supply the necessary amount of hydraulic fluid to the steering motor.